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This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): John L. Myers Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Myers, J. L. Search for Related Content PubMed Articles by Myers, J. L. Related Collections Cardiac - pharmacology Related Article

Ann Thorac Surg 2001;72:2093-2094
© 2001 The Society of Thoracic Surgeons

Invited commentary

^a Department of Pediatric Cardiovascular Surgery, Children’s Hospital, The Milton S. Hershey Medical Center, 500 University Dr, Box 850, Hershey, PA 17033-0850, USA

e-mail: jlmyers{at}psu.edu

The authors have very nicely demonstrated the hemodynamic and metabolic advantages gained by the use of inspired CO₂ in the postoperative management of neonates with complex single ventricle complexes with a "shunted" or parallel circulation.

Hypoventilation alone to achieve hypercarbia can be problematic because babies often have secretions and airway edema following open-heart surgery and cardiopulmonary bypass. Mechanical hypoventilation in this setting frequently results in atelectasis with a decrease in alveolar and arterial saturation. In this clinical setting FiO₂ is often increased to maintain arterial saturations at 75% to 80%. Increasing tidal volume to combat atelectasis results in increased alveolar ventilation and a fall in arterial pCO₂. Adding more PEEP increases mean airway pressure.

The inspired CO₂ concept is actually quite simple. The technique used by these and other authors separates the mechanical aspects of ventilation (ie, tidal volume, rate, and end expiratory pressure) from the control of arterial pCO₂. The ventilator is set to deliver a generous tidal volume at a rate of 14–20 breaths per minute and positive end expiratory pressure of 3 Torr to 5 Torr. This minimizes the development of atelectasis. A chest x-ray confirms well-expanded lungs. FiO₂ is usually kept at 21% to 25%. Thereafter arterial pCO₂ is controlled by adjusting the inspired CO₂ to achieve the target arterial pCO₂ that will help achieve optimal balance of pulmonary and systemic blood flow.

The authors are to be commended for their study that demonstrates improved systemic oxygen delivery when inspired CO₂ is delivered to the mechanical ventilator without a change in minute ventilation.

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Hemodynamic effects of inspired carbon dioxide after the Norwood procedure

Scott M. Bradley, Janet M. Simsic, and Andrew M. Atz
Ann. Thorac. Surg. 2001 72: 2088-2093. [Abstract] [Full Text] [PDF]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): John L. Myers Permission Requests Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Myers, J. L. Search for Related Content PubMed Articles by Myers, J. L. Related Collections Cardiac - pharmacology Related Article